The George Institute For Global Health
United Kingdom

Tackling hypertension in China via changing its salt habit

High salt consumption is closely related to hypertension, one of the most serious risk factors of chronic disease such as cardiovascular disease (CVD). It is estimated that if the average salt intake in China per person can be reduced by 1 gram, 5% of the total deaths caused by CVD can be effectively prevented.

However, high salt intake has been part of the nation’s food culture for a long time and will be difficult to be changed in China, a developing country with a large population. Chinese people are ‘addicted’ to salty cuisines, consuming 12 gram salt per day per person which appallingly surpasses the daily maximum recommended by World Health Organization (WHO), that is, 5g; China also bears a severer CVD burden. According to Report on China Cardiovascular Disease 2013, 1 out of 5 adults has CVD; 40% of the deaths are caused by CVD.

On September 12th, Science Magazine published an article discussing the feasibility of improving population’s health via changing the dietary habits in China. Cardiologists and epidemiologists from both China and Australia participated in the discussion.

All countries in the world are facing difficulties to reduce the salt intake among populations. Different strategies have been designed and implemented accordingly. In developed countries, where most salt consumed in the diet comes from processed and restaurant foods, the efforts to reduce salt intake and hypertension have been focused on pressuring the government and food industry to reduce the salt content of these foods. In China, particularly rural areas, salt is primarily from home cooking. Therefore, it is an ideal situation to implement lifestyle interventions. Yet, the awareness and control rates of hypertension are still low in these areas where resources and health care infrastructure are difficult to access. Hence, salt reduction initiatives in these areas will be challenging.

A large-scale cost-effective health care strategy targeting the greatest population has become one of the prioritized tasks the government needs to tackle.

At present, a large-scaled randomized controlled trial - The China Salt Substitute and Stroke Study (SSaSS), is underway in northern rural areas in China. The study aims to find out if the low-sodium salt substitute can reduce the morbidity and mortality of stroke. One of the Principal Investigators (PI) [who?], a cardiovascular specialist at Peking University Clinical Research Institute and Senior Research Fellow at The George Institute for Global Health at Peking University Health Science Center,  said that the study would recruit 21000 high risk patients with stroke and hypertension from 600 villages in northern China and Tibet, and would be randomized into control and intervention group at 1:1. Patients and their families in the intervention group wouldreceive a salt substitute for free to replace the regular salt. The study would last for 5 years, investigators would follow up with the participants and record stroke and other cardiovascular events. Urine samples would also be collected to reveal changes in sodium and potassium intake. Professor WU [need his full title] said, previous studies have shown that low-sodium salt substitute can lower the blood pressure, however, SSaSS will be the largest ever study of a dietary intervention for stroke prevention worldwide.

At the same time, the health care reforms in China have stepped into a critical moment. In 2009, the Chinese government initiated a national program - National Basic Public Health Services, to provide standard management to patients with hypertension and other several conditions through its primary care system. It includes providing free blood pressure checks and partially subsidized drugs to hypertension patients. China has also set a goal for salt reduction to 9 grams per day by 2015. The reforms bring opportunities and hope, but deeper reforms are necessary to the final success.

Professor Bruce NEAL from The George Institute for Global Health and University of Sydney, another PI of the study, said that if the SSaSS study was effective, proving that low-sodium salt substitute could reduce the morbidity and mortality of stroke, it would provide concrete scientific evidence to policy makers, help get prepared to promote low-sodium salt substitutes, including relevant policy making, and low-sodium salt substitutes subsidies (the price of low sodium salt subsidies is as twice as expensive to that of regular salt). 

In addition to that, China adopts a monopolistic salt supply system. To convince the salt industry to gradually reduce sodium content and improve the salt substitute formula would be an alternative strategy.

Around the world, 80% of cardiovascular disease mortalities take place in low and middle income countries where many hypertensive patients cannot afford the cost of treatment. Therefore, prevention of the disease is undoubtedly critical. Populations in mid and eastern Asia have a high salt culinary culture. The use of low sodium salt substitutes is expected to improve their health status.

Click here to read the full article on Science Magazine